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The middle "siltstone-coal facies" monitoring holes are designated by an "M" following the hole <br />number. These monitor holes are open through the interval containing the D Seam and B <br />Seam. <br />Monitor hole TW2-17M was by-passed by mining first in November 1985 but was not <br />intercepted in the workings. It is apparently located in a pillar completety surrounded by open <br />workings. At that time it showed virtually no response to room-and-pillar mining. In February <br />1988 longwall panel 1 was mined to within about 900 feet of this hole. Obviously, longwall <br />mining disrupts the mined zone more than room-and-pillar mining, and the water level in <br />TW2-17M did show a response to mining at that time. The water level decreased 9.0 feet <br />during the 2002-03 period. This followed a decrease of 39.7 feet in 1998-99, 11.2 feet in <br />1999-2000, 5.4 feet in 2000-2001, and 2.6 feet in 2001-2002. The 1998-99 water year <br />showed a substantial change probably due to the mining of LW-12. <br />Hole 32-7M became dry after longwall mining passed directly beneath this hole in 2001. <br />The water level in Hole 30-8M increased 11.2 feet. The cause for the rise is unknown but <br />could represent a recovery in the water table since 1997-98's 46 foot decrease. Mining has <br />not advanced into this area to date. <br />All other middle facies holes experienced what is considered normal fluctuations of water <br />level. <br />The hydrographs of the "lower sandstone facies" are designated by the letter "L" following the <br />hole number. <br />Hole 32-7L was mined through by the longwall in early 2001. Prior to being mined through the <br />hole was plugged to above the coal seam with Baroid Holeplug. <br />All other lower facies holes experience what is considered normal seasonal fluctuations of <br />water level. <br />From the baseline data, all three zones should be classified as "aquitards" in that they will <br />yield water but at very slow rates. Mining in the B Seam so far has encountered only small <br />flows of water and the mine is essentially dry. Typical flows are in the order of 6 to 8 gpm with <br />occasional short term increases when localized perched water tables are encountered. <br />Previously, water leaking out of caved areas was routed to the sumps at the end of gateroads. <br />No underground water has been pumped out of the mine since the January 31, 1996 <br />underground fire. <br />6 <br />